Di-tricyclodecane (5, 2, 1, 02, 6)-8, 8&#39;-ether-4, 4&#39;-dicarboxylic acid



United States Patent DI-TRICYCLODECANE (5,2,1,0 ')-8,8'-ETHER-4,4'-

- DICARBOXYLIC ACID No Drawing. Application August 15, 1956 Serial No. 604,079

Claims priority, application Germany August 18, 1955 1 Claim. (01. 260-514) This invention relates to and has as its object the production of di-tricyclodecane (5,2,1,0" )-8,8'-ether-4,4'- dicarboxylic acid, which has been found to constitute a valuable dicarboxylic acid which is particularly well suited for the production of monoesters and polyesters to be used as bases for lacquers, plastics, placticizers, lubricants and for similar uses.

It is known to produce 8-hydroxy-tricyclodecene-4(5, 2,1,0) from dicyclopentadiene by the addition of water in the presence of sulfuric acid. This reaction is accompanied to a minor degree by a splitting off of water between two molecules of the secondary alcohol formed. The splitting off of Water results in the formation of ethers and other higher boiling products. When recovering the secondary alcohol by distillation, resinous masses are obtained as the distillation residues, which have hithertofore been considered worthless by-products.

The side reaction may, of course, be made a main chemical reaction by splitting oil water from 8-hydroxytricyclodecene-4(5,2,1,0 with the formation of ether or by condensing it with dicyclopentadiene. The reaction may be represented as follows:

1 IT i T +rno H I 4 a e-s HO T a Dieyclopentadiene S-hydrorytrlcyclode cane-4 (5,2,1,0

B-hydroxytricyclodecene- It has now been found in accordance with the invention that a valuable high-molecular weight dicarboxylic acid may be produced from this ether by-product, which has hithertofore been considered worthless.

In accordance with the invention, the di-tricyclodecene- 4,4(5,2,1,0 )8,8'-ether is subjected to a'catalytic dialdehyde synthesis with water gas, i.e., an oxo-synthesis,

so-that one methylal group is added to each of the double Patented Apr. '1,

bonds at the 4-position in accordance with the following reaction:

qil -GD qil lib Dl-tricyclodecane 6,2,1,0 8,8 ether-4,4 di-methylal The ether dimethyl-al obtained which is believed to constitute a novel compound is subsequently subjected to a catalytic treatment with hydrogen, thereby converting it into the corresponding dialcohol and the latter is subsequently subjected to a treatment with molten alkali and converted into the corresponding dicarboxylic acid by treatment with any organic or inorganic acid at a pH value below that of the ether dicarboxylic acid.

The conversion proceeds in accordance with the fol lowing reaction scheme:

l) 0% I -T G lib l i fil li The novel ether dicarboxylic acid formed may be designated di-tricyclodecane 5,2,1,0 -s,s' ether-4,4di-

carboxylic acid and is first obtained in crystalline form containing water of crystallization. At a temperature ofabout 70 C. and under vacuum as, for example, a

p pressure of 20 mm. Hg as produced by a water jet pump,

the acid loses its water of crystallization and becomes amorphous. The acid is very temperature-resistant and will be resistant to temperatures of as high as about 300 C. in the absence of oxygen. The acid has the follow spending dimethylol compound lay-hydrogenation; it I Molecular weight of the di-n-butylester 477 (corrected 287').

Instead of converting the dialdehyde into the corre possible to directly treat the raw dialdehyde with the molten alkali. In this case, however, it is difiicult to separate the dicarboxylic acid from the mono-derivatives and thick oils, which are also present in the raw aldehyde. If, however, the dimethylol compound is treated with molten alkali, it can first be freed from undesirable byproducts by fractional distillation, and can thus be further processed in pure form. For the same reason, the production of dicarboxylic acid by the oxidation of the dialdehyde with an oxidizing agent, as, for example, with nitric acid or atmospheric oxygen, is not completely satisfactory.

In accordance with the preferred mode of operation for the production of the dicarboxylic acid, the residue obtained in the production of 8-hydroxy tricyclodecene is distilled, so that roughly 76% of the quantity charged is distilled off with distillation being efiected at a pressure of about 2 mm. of mercury at a temperature up to 196 C. with no fractionation. From this known operational step a yellow oil having the following characteristics is obtained:

Iodine number by Kaufmanu 168 Neutralization number 0.1 Ester number 1.2 Hydroxyl number 67 This oil may be fractionated, which results in the separation of 62.2% by weight of di-tricyclodecene-4,4'(5, 2,1,0 )8,8'-ether. The ether is then subjected to a dialdehyde synthesis, as, for example, by diluting the same with equal parts of benzene and contacting the mixture with carbon monoxide and hydrogen at a temperature between about 135 and 150 C. and at a pressure of about 150-300 atmospheres in the presence of a catalyst which supplies cobalt carbonyl hydrogen for a period of time of between about 2 and 3 hours. This results in the addition of methylal groups in the 4,4'-position. The dialdehyde is then subjected to a catalytic hydrogenation which converts the aldehyde groups into the corresponding alcohols. The dimethylol separates from the benzene solution as a lower, heavier layer after the addition of aliphatic saturated hydrocarbons, as, for example, hexane or heptane. Upon separation of this lower, heavier layer, the same may be purified with further amounts of heptane resulting in about 90% pure raw diol. To obtain the diol in pure form, the same is subjected to a short distillation under vacuum (0.5 mm. Hg) at 205-214 C. The distillate obtained is a solid, resinous, readily brittle, clear and transparent substance, having the following characteristics:

Iodine number 0.

Neutralization number 0.3.

Ester number 2.0.

Hydroxyl number 313 (corrected 323 for di-tricyclodecane (5,210) 4,4'-dimethylol-8,8'-ether) Iodine color number -1. Melting point 50/ 5 1 C.

This intermediate product is novel and has not yet been described in the literature. The yield of the diol is 70-85% based on the di-tricyclodecene-4,4(5,2,1,0 )8, 8'-ether.

The treatment of the diol with molten alkali is preferably etfected at a low temperature. The splitting off of hydrogen commences at about 210 C. and practically terminates at 250 C., so that the diol charge is converted into the corresponding dicarboxylic acid salt. To convert the last residues of the diol the temperature of the melting bath may be increased to about 300 C. without deteriorating the compound.

It is then preferable to cool the compound to about 150 C. and to inject about 150% of water-based on the quantity of diolcharged into the hot melt to thereby convert the same into a paste which can be easily handled.

The treatment with molten alkali may also be efiected in the presence of a neutral hydrocarbon, as, for example, octane or its homologues.

After being removed from the melting operation, the salt paste is diluted with water to four to five times its volume. To obtain a pure white ether dicarboxylic acid, the excess alkali is neutralized to a pH value of 8, and then the salt paste is hydrogenated at 210 C., using a known hydrogenation catalyst, preferably a nickel magnesia kieselguhr catalyst (100210250). Thereby the brown, aqueous salt solution is brought to an iodine color number of 0. By acidifying the same with, for example, hydrochloric acid or sulfuric acid to pH 5.9, small amounts of dicarboxylic acid ether compounds and monocarboxylic acid ether compounds containing impurities, precipitate from the purified solution. Following this, the main precipitation of the crystalline clear water containing di-tricyclodecane (5,2,1,0 )-8,8'-ether-4,4' dicarboxylic acid is effected with the further addition of acid while stirring.

Drying in a desiccator at 70 C. under a vacuum of 20 mm. mercury results in the formation of the anhydrous, amorphous ether dicarboxylic acid having the character istics given above.

The ether dicarboxylic acid (C H O is useful'in all reactions which require the presence of carboxyl groups. As mentioned, the acid is particularly suitable for the production of monoesters and polyesters as bases for lacquers, plastics, plasticizers, lubricants, and for similar uses. The ether dicarboxylic acid is relatively insoluble in ethers, but soluble in cold benzene hydrocarbons, ketones, alcohols, and chlorinated hydrocarbons. The dicarboxylic acid is sparingly soluble in acetic acid when cold and readily soluble when hot.

The following examples are given by way of illustration and not limitation: 1 Example 1 1790 grams of a highly viscous, dark brown residue was filled into a 2 liter flask. This residue had been obtained in amount of about 10% by processing by distillation, 8-hydroxy-tricyclodecene-4(5,2,1,0 obtained by the addition of water to dicyclopentadiene. The 2 liter flask was provided with an empty tube of 30 cm. length serving as a column. The distillation was effected up to a vacuum of 0.5 mm. Hg with total condensation of the distillate. The maximum temperature was 195' C. as measured at the transition point. A distillate of yellow color and lubricating oil consistency was obtained in amount of 1360 grams (76%). The bottoms product remaining in the flask was a solid, dark brown, resinous residue.

The distillate in amount of 1290 grams was fractionated in a packed column of 30 cmrin length with the addition of about 1% of magnesia. The products obtained'with separation of the intermediate fractions were as follows:

Grams 8-hydroxytricyclodecene 4 189 di-Tricyclodecene-4,4(5,2,1,0=- )8,8 ether 1032 Higher polymers 50 The boiling range of the ether was between and C. (at 0.7 mm. Hg).

646 grams (600 cc.) of this di-tricyclodecene-4,4'(5,2, 1,0 )-8,8 ether were diluted with 600 cc. of toluene. The mixture, together with 600 cc. of aqueous cobalt sulfate solution (15 grams of Co/liter), 25 grams of iron powder and 2 grams of hydroquinone, was filled into an autoclave with stirrer having a capacity of 3.6 liters. After displacement of the air from the autoclave, the same was filled with water gas from a cylinder to a pressure of 200 atmospheres. The autoclave wasthen heated to 153 C. while stirring. The absorption of gas started at 140 C. and was terminated after 2 hours. About9 mols of CO-i-H were absorbed with the amount charged of di-tricyclodecene-4,4'(5,2,1,0 )-8,8' ether being 2.04 mols.

Upon termination of the gas absorption, the autoclave was cooled, the product was removed and separated from the aqueous catalyst solution by decantation. The dilute raw dialdehyde ether had the following characteristics:

Iodine number Carbonyl number 153 Hydroxyl number 28 Iodine number 2 Neutralization number 0.4

Ester number 5.3 Hydroxyl number 281 Carbonyl number 7 300 grams of this raw diol ether, together with 154 grams of KOH, were filled into a copper-lined autoclave with stirrer having a capacity of 2.8 liters. The autoclave was heated to 240 C. The evolution of hydrogen. started already at 200 C. and was practically terminated after about 30 minutes at a final temperature of 250 C. A total of 3.4 mols of hydrogen was obtained. After cooling of the melt to 150 C., 500 cc. of water were forced into the autoclave while stirring. The aqueous salt paste was made up with water to 2.5 liters and brought to pH 7.0 by adding dilute hydrochloric acid. This resulted in a precipitate in amount of 60 grams, consisting of unsaponifiable matter and monoether-carboxylic acid. The neutralized solution was shaken out two times with 150 cc. of benzene to remove any unsaponifiable components still present. Further addition of dilute hydrochloric acid to pH 5.9 resulted in a second precipitate, the amount of which was likewise 60 grams. The characteristics of the precipitated dried substances were as follows:

1st 2nd Preclpi- Precipltate tate Iodine number 22 2 Neutralization number... 79 226 Ester number 0 0 Hydroxyl number 8 1V The prepurified ether-dicarboxylic acid salt solution was then completely precipitated by adding further amounts of hydrochloric acid until the pH value was 2.0.v This resulted in 310 grams of crystalline, moist ether dicarboxylic acid which became amorphous upon drying at 70 C. under vacuum. The amount obtained was 170 grams with the following characteristics:

2 kilograms of dicyclopentadiene and 3 kilograms of 25% sulfuric acid, in a 6 liter flask, were refluxed while stirring. Following this, suflicient water was distilled off that the concentration of the sulfuric acid increased to Ester number 12 Hydroxyl number 90 Carbonyl number 27 w'grams of a fraction with the following characteristics 6 furic acid and washingwith sodium hydroxide solution and water had the following characteristics:

Hydroxyl number 214 Iodine number Fractionation of this product resulted in 30% of di-' tricyclodecene-4,4'-(5,2,1,0 )-8,8'-ether (650 grams) in addition to 55% of non-etherified 8-hydroxytricyclodecene-4.

538 grams of this ether were diluted with the same volume of toluene. After the addition of 10% by volume of Fischer-Tropsch catalyst and 2 grams of hydroquinone, it was subjected to the Oxo-synthesis in the manner described in Example 1 except for the temperature which was only 135 C. This was followed by the hydration which was etfectedfor 2 hours at 210 C. with the addition of 10% by volume of water to precipitate dissolved metals and to cleave the a cetals.. The hydratedv product had the following characteristics:

Iodine number 3 Neutralization number 1 Ester number 14.5 Hydroxyl number 24 Carbonyl number 132 The hydrogenation was effected as described in Example l.

which was similar to neutral oil and had the following.

characteristics:

Iodine number 24 Neutralization number 1 The distillation of the di-tricyclodecane(5,2,1,0)-8, 8'-ether-4,4-dimethylol was effected at 0.5 mm. Hg in a short-run distilling apparatus. At 205-215 C., 400

was obtained:

Hydroxyl number 314 (corrected 323). Neutralization number 0.1.

. Ester number 1.2. Iodine number 1.

about 37%. The refluxing was then continued for two;

hours. The product obtained after separation of the sub The first runnings amounted to 12 grams and the.

350 grams of the distillatewere mixed with 350 cc. of cetane and 135 grams of caustic potash and melted in the manner described in solid residue to 38 grams.

nickel-magnesia-kieselguhr catalyst 1O 50). Separation of the catalyst by filtration resulted in a waterwhite filtrate with an iodine color number of 0, which was precipitated at pH 5.9, and, after separation of the me cipitated substances, subjected to final precipitation in the manner described in Example 1, until the pH value was 2. After drying under vacuum, there were obtained 252 grams of di-tricyclodecane(5,2,1,0 )-8,8' ether-4,4-dicarboxylic acid having the following characteristics:

Neutralization number 290 (corrected 299). Iodine number 0.

Esternumber 0.

Melting point C.

4 As in Example 1, the hydrogenated productwas extracted two times by shaking, using 300 cc. ofhep- Example 3 A suitable ester-lub-oil (III) for vacuum pumps and compressors is obtained from di-tricyclodecane(5,2,l, )-8,8-ether-4,4'-dicarboxylic acid (I) and 3,5,5-trimethylhexanol-l (II) in the following procedure:

HOOC- CODE CHxHH HI? 374 g. (I) (1 mol) +630 g. (II) (2.19 mol) were refluxed with 1 g. p-toluenesulfonic acid and 300 ml. toluene in a 2 litre round flask with a water precipitator attached. After 12 hours a test showed an acid number NhGO and a hydroxyl number OHZ=68. Following this procedure 60 g. (II) and 2 g. borontrifluoride were added. After another half hour of refluxing the water precipitation was finished. The ester (III) was then scrubbed with 1% potassium hydroxide up to an acid number of 0.07 and was obtained at 0.03 torr in a shortway-distillating-(molecular)apparatus at 193220 C. Characteristics of the ester lub oil obtained were:

The ester (III) is also very suitable as a blending component with other ester oils. With a tricyclodecane(5,2, l,0 )methylol-4-valeric acid ester C H O (structure IV):

r at H O H H H IV showing only a very low viscosity of V =7.4 cs., a mixture of 30 parts by weight (III) and 70 parts by weight (IV) has the following characteristics:

Density D 1.024.

Viscosity V 15.7 cs. (calc. 15.5). Vapor point VP 1.88.

Flash point Flp 165 C.

Pour point Stp 50 C. (calc. 50.5).

The viscosity and the solidification point of the mixture has been calculated as an arithmetic median. Ester (III) may therefore be used as a high viscous blending component dealing with mixed ester oils.

Example 4 r r no-ok (ll-OH O H H v HOOC(CH- )2-CHa VI Density D 1.077.

Refractive index n 1.5017.

Boiling range 238-245 C. (0.02 torr). Flash point Flp 277 C.

Pour point Stp ..-a 5 C.

.ammomouomolonm III Viscosity V 215 cs.-28.3 E. Viscosity V 46.4 cs.-6.16 E. Molecular weight 477 (calculated 486).

Example 5 The preparation of a polyester from di-tricyclodecane- (521,0 )8,8-ether-4,4-dicarboxylic acid was carried out as follows.

In a round flask with a nitrogen inlet joint and a short nitrogen and water outlet joint, including a joint for thermometer and an agitator ground in, heated externally by a semi circular shaped hood including an adjusting device, using 25 g. di-tricyclodecane(5,2,l,0 ')-8,8'- ether-4,4-dicarboxylic acid (moist) (acid number, NZ=160), 4.1 g. glycol (excess which partly distills over), 0.1 g. oxalic acid, heating this mixture for one hour under agitation at 100 C. and after 12 hours at 150 C. and additional 6 hours at ZOO-210 C., a clear polyester was obtained. The polyester product could be broken up into a white powder and had the characteristics: acid number NZ 7.3; hydroxyl number OHZ 7; melting point 124-130 C.

The product ground in the mortar was subjected to a thermal post-treatment at 270 C. and 1 mm. mercury level under nitrogen protection. For heat transfer a phthalate bath was used. The polyester thereby obtained (melting point 124-135 C.) had a hard shining surface and was especially suited for use as a lacquer component. Its molecular weight as calculated from the final figures was about 8000.

Example 6 In the same apparatus as shown in Example 5, 20 g. di-tricyclodecane(5,2,1,0 8,8'-ether 4,4 dimethylol (0.057 mol), 2.25 g. adipic acid (0.015 mol), 5.17 maleic acid anhydride (0.015 mol) were first agitated for one hour at 100 C. under nitrogen protection, then for 18 hours under nitrogen protection at 150 C. This resulted in heavy condensation and especially polymerisation. The final product was soluble only in the amount of one part in solvents such as benzyl-benzene-chloride and diphenylether. Essentially'a swelling occured. On heating to temperatures C. only slight sintering occured, whereas the main part did not melt until 320 C. The polyester was of a slightly yellowish colour, very hard but still somewhat brittle since the esterification had already progressed too far.

' 10 For the copolymerisation with styrol there was charged: CH CH 1 g. of the aforementioned polyester (ground) /CHl-C OH: 0 (EH-CH2 1 g. styrol fractionated I I l 0.02 g. hardening paste (benzoylperoxide-phthalate) H000 OH CH2 CH2 0 COOH 5 011F011 OH-O-OH on-o 0.1 g. quinone. After 5 hours of heating in a phthalate bath to 100- CH C 120 C. under nitrogen protection the styrol had reacted References Cited in the file of this patent and was copolymerised. The polyester treated in this way had a yellowish colour, was hard and had lost its 10 UNITED STATES PATENTS brittleness. 1,968,300 Kyrides July 31, 1934 We claim: 2,610,211 Darragh et a1. Sept. 9, 1952 Di-tricyclodecane(5,2,1,0) 8,8 ether 4,4 dicar- 2,749,328 Cline June 5, 1956 boxylic acid having the following formula UNITED STATES PATENT OFFICE Certificate of Correction Patent No. 2,881,208 April 7 1959 Karl Biichner et al.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 2, lines 24: to 27, the reaction scheme should appear as shown below instead of as in the patent- H H +2H: o=mCL6 J a 0:0

column 7, line 61, after Ewample 4 insert the following paragraph:

A high viscous distillable water clear ester (VII) as softener for polyesters, mixed polymerisates and cellulose esters is obtained by esterification of the dit(ri7c]3l7)clodecane (5,2,1,O -8,8-ether-l, l-dimethylol (V) with butyrlc acid Signed and sealed this 15th day of September 1959.

[SEAL] Attest: KARL H. AXLINE, ROBERT C. WATSON, Attestz'ng Ofliaer. Commissioner of Patents. 

